Muzzle attachment for machine guns



' July 19, 1938. F. "r. MOORE MUZZLE ATTACHMENT FOR MACHINE GUNS Original Filed Nov. 18, 1935 lllllllilllllll W t 0777 51y iiiillllliiillllllll .7271 51 7 Z: 01 Frederick KNEE/r5 Patented July 19, 1938 UNITED STATES PATENT QFFEQE MUZZLE ATTACHlVIENT FOR MACHINE GUNS of Connecticut Original application November 18, 1935, Serial Divided and this application April 5, 1937, Serial No. 135,003

6 Claims.

This invention relates particularly to an attachment adapted to be associated with the muzzle of a gun barrel and connectible with a guide or jacket surrounding the barrel. The general object of the invention is to provide means whereby the attachment as an entirety can be readily connected to or removed from the supporting guide or jacket.

This application constitutes a division of my co-pending application for Machine gun, Serial No. 50,387, filed November 18, 1935.

In the accompanying drawing I have shown two embodiments of the invention, but it will be understood that the drawing is intended for illustrative purposes only and is not to be construed as defining or limiting the scope of the invention, the claims forming a part of this specification being relied upon for that purpose.

Of the drawing:

Fig. l is a combined side and longitudinal sectional view of an attachment embodying the invention, together with the forward portions of a machine gun barrel and the surrounding guide or jacket.

' Fig. 2 is a transverse sectional view taken along the line 22 of Fig. 1.

Fig. 3 is a view similar to Fig. 1 but showing the lock nut and lock ring in their forward positions.

Fig. 4 is a View similar to Fig. 2 but showing the parts in the relative positions which they occupy prior to disassembly.

Fig. 5 is a view similar to Figs. 1 and 3 but showing the bearing sleeve and associated parts removed from the barrel jacket.

Fig. 6 is a View similar to Fig. 1 but showing an alternative embodiment of the invention.

Fig. 7 is a transverse sectional view taken along the line 1-'l of Fig. 6.

Fig. 8 is a View similar to Fig. 6 but showing the lock nut in its forward position.

Fig. 9 is a view similar to Figs. 6 and 8 but showing the bearing sleeve and associated parts removed from the barrel jacket.

The present invention is particularly applicable to a machine gun having a longitudinally reciprocating barrel which is surrounded by a stationary guide or jacket. Such a gun is shown and described in my aforesaid pending application. The forward portion of the reciprocating barrel is shown in the drawing at I; and the forward portion of the stationary guide or jacket is shown at 2, the said jacket extending nearly to the forward end of the barrel.

The barrel I has a diameter at its front end portion which is smaller than its maximum diameter, and a bearing 3' is provided which engages this front end portion of the barrel. The barrel guiding bearing 3 is formed as a part of a bearing sleeve 5, the said sleeve being detachably connected with the jacket as hereinafter described in detail. At the front of the barrel is a portion adapted for convenient engagement to effect barrel rotation, this portion being in front of the front end of the jacket and being therefore accessible with the jacket in place. As shown the said portion is provided with radial holes 6. When the sleeve 5 has been removed, as indicated in Fig. 5, the front end portion of the barrel I is exposed, and by means of a spanner wrench engaging the holes 6 the said barrel may be turned and thus unscrewed from the parts of the gun with which it is connected. Similarly, upon being turned in the other direction, the barrel can be again connected.

The barrel l is relatively heavy, its large mass being relied upon to avoid too rapid heating. A heavy barrel such as shown has the advantage that it heats less rapidly, but it has the disadvantage that it recoils more sluggishly and thus tends to cause the mechanism of the gun to operate more slowly than it otherwise would. In order to obtain the advantages of the heavy barrel and to avoid the ordinary disadvantages thereof, I preferably provide means at the front of the barrel for forming a chamber which will receive the gases of explosion and cause them to react upon the barrel to expedite the recoil thereof. As shown, the sleeve 5 is extended forward and carries at the front a plug 1 which is apertured at 8 in alignment with the bore of the barrel to permit the passage of the bullet. The plug 1 preferably has threaded engagement with the sleeve 5, as shown. From an inspection of Fig. 1 it will be apparent that there is formed a gas chamber 9 into which the gases of explosion will expand immediately upon the escape of the bullet from the barrel. The expanding gases in the chamber 9 react upon the front surface of the barrel, tending to push the barrel rearward and thus expedite the recoil thereof.

Inasmuch as the sleeve 5 and the plug 1 which form the gas chamber 9 are detachably connected with the jacket 2 they do not interfere with the ready removal of the barrel from the gun in the forward direction. Notwithstanding its large mass, the barrel I may become heated to such an extent that it is desirable to remove it and replace it by a cool barrel. This can be readily done by first removing the sleeve 5 With its associated parts and then unscrewing the barrel by means of a spanner wrench. A substitute cool barrel can be put in place in the manner already described and then the sleeve 5 with its associated parts can be replaced and attached to the jacket- In order to facilitate the removal and replacement of the barrel, I provide special means permitting the quick detachment and attachment of the bearing sleeve 5. One such construction is shown in Figs. 1 to 5. As shown, the jacket 2 is provided with interrupted threads, and the bearing sleeve 5 is similarly provided with interrupted threads. When the bearing sleeve is in place the threads are engaged, as clearly shown in Fig. 2. In order that the sleeve 5 may be prevented from unintended turning by reason of vibration or otherwise, I provide a lock nut 10 and a lock ring H. The lock nut ii] is engaged with the threads on the bearing sleeve 5 and the adjacent lock ring H is freely movable longitudinally with respect to the sleeve but is held against relative rotation by means of a stud I2 which engages a longitudinal groove I3 in the sleeve. Interengaging means are provided on .the jacket 2 and on the lock ring H for preventing relative rotation of the latter, and as shown in Figs. 1, 3 and 5 the interengaging means comprise an annular series of serrations on the front of the jacket 2 and a similar annular series of serrations on the rear of the ring l I. With the serrations interengaged, as shown in Fig. l, and with the lock ring H pressed rearward by the lock nut ID, as shown in the same figure, it will be evident that the sleeve 5 is positively held against rotation.

' In order to remove the sleeve 5, the lock nut I0 is turned by means of a spanner wrench or ,otherwise to the forward position shown in Fig. 3, and the lock ring H is also moved forward so as to disengage the serrations thereof from the serrations on the jacket 2. The sleeve 5 can then be given a quarter-turn so as to bring the interrupted threads thereof out of engagement with the interrupted threads of the jacket, as clearly shown in Fig. 4. With the threads thus disengaged, the sleeve and the parts associated therewith can be moved forward and completely disengaged from the jacket, as shown in Fig. 5.

After the barrel has been taken out in the manner already described, and after a substitute cool barrel has been put in place, the sleeve 5 can be again attached to the jacket by reversing the steps which have been described. After the threaded portion of the sleeve has been inserted in the jacket, the sleeve is turned to bring the interrupted threads again into engagement, as shown in Fig. 2. Then the lock nut ID is turned sufficiently to force the lock ring I! rearward and thus engage its serrations on the jacket.

The construction shown in Figs. 6 to 9 is very similar to that shown in Figs. 1 to 5. The essential difference is that no interengaging ser-' rations are provided, the engaging surfaces of the jacket 2 and of the lock ring H being smooth. The said ring H is, however, provided with serrations on its outer or peripheral surface, and a resilient latch I 4 is provided on the jacket, which latch is adapted to enter the serrations on the lock ring. The serrations are preferably V-shaped so that when the ring is turned the latch I4 is caused to snap into the successive notches and thus tend to hold the ring in any position of adjustment.

When it is desired to remove the sleeve 5, the lock nutlfl is turned in the manner already described, being thus moved to its forward position, as shown in Fig. 6. Then the sleeve is given a quarter-turn to disengage the interrupted threads thereof from the interrupted threads of the jacket, it being understood that the lock ring H turns with the sleeve. The sleeve and the associated parts can then be detached, as indicated in Fig. 9. The sleeve and associated parts can be again attached by inserting the forward portion of the sleeve in the jacket and giving the sleeve a quarter-turn. The sleeve can be locked by turning the lock nut ii] to move it from the position shown in Fig. 8 to the position shown in Fig. 6.

What I claim is:

1. In a machine gun, the combination of a longitudinally reciprocable barrel, a barrel jacket surrounding the barrel and a barrel guiding bearing carried by the jacket near the front end thereof. the said jacket and bearing having interrupted threads permitting the latter to be readily engaged with or disengaged from the former, a lock nut carried by the bearing and having threaded engagement with the thread thereof, a lock ring longitudinally movable relatively to the bearing but held against rotation relatively thereto, the said lock ring being positioned to be pressed by the lock nut against the end of the jacket when the bearing and jacket are in normal relationship, and interengaging means on the jacket and lock ring for preventing the latter from rotation relative to the former.

2. In a machine gun, the combination of a longitudinally reciprocable barrel, a barrel jacket surrounding the barrel and a bearing sleeve carried by the jacket near the front end thereof and having a bearing engaging the front portion of the barrel, the said jacket and sleeve having interrupted threads permitting the latter to be readily engaged with or disengaged from the former, a plug at the front of the barrel carried by the bearing sleeve and removable therewith, the said plug having an aperture in alignment with the bore of the barrel and serving in conjunction with the sleeve to form a gas chamber at the front of the barrel, a lock nut carried by the sleeve and having threaded engagement with the thread thereof, a lock ring longitudinally movable relatively to the sleeve but held against rotation relatively thereto, the said lock ring being positioned to be pressed by the lock nut against the end of the jacket when the bearing and jacket are in normal relationship, and interengaging means on the jacket and lock ring for preventing the latter from rotation relative to the former.

3. In a machine gun, the combination of a longitudinally reciprocable barrel, a barrel jacket surrounding the barrel and a barrel guiding bearing carried by the jacket near the front end thereof, the said jacket and bearing having interrupted threads permitting the latter to be readily engaged with" or disengaged from the former, a lock nut carried by the bearing and having threaded engagement with the thread thereof, a lock ring longitudinally movable relatively to the bearing but held against rotation relatively thereto, the said lock ring being positioned to be pressed by the lock nut against the end of the jacket when the bearing and jacket are in normal relationship, and interengaging means formed integrally'with the jacket and lock ring respectively for preventing the latter from rotation relative to the former.

4. In a machine gun, the combination of a longitudinally reciprocable barrel, a barrel jacket surrounding the barrel and. a barrel guiding bearing carried by the jacket near the front end thereof, the said jacket and bearing having interrupted threads permitting the latter to be readily engaged with or disengaged from the former and the said jacket having an annular series of serrations at its front end, a lock nut carried by the bearing and having threaded engagement With the thread thereof, and a lock ring longitudinallymovable relatively to the bearing but held against rotation relatively thereto, the said lock ring being positioned to be pressed by the lock nut against the end of the jacket and having at its rear an annular series of serrations adapted to interengage with the serrations on the sleeve, and interengaging means on the jacket and lock ring for preventing the latter from rotation relative to the former.

5. In a machine gun, the combination of a longitudinally reciprocable barrel, a barrel jacket surrounding the barrel and a barrel guiding bearing carried by the jacket near the front end thereof, the said jacket and bearing having interrupted threads permitting the latter to be readily engaged with or disengaged from the former, a lock nut carried by the bearing and having threaded engagement with the thread thereof, a lock ring longitudinally movable relatively to the bearing but held against rotation relatively thereto, the said lock ring being positioned to be pressed by the lock nut against the end of the jacket when the bearing and jacket are in normal relationship, and a latch on the jacket for engaging the ring to prevent relative rotation thereof.

6. In a machine gun, the combination of a longitudinally reciprocable barrel, a barrel jacket surrounding the barrel and a barrel guiding bearing carried by the jacket near the front end thereof, the said jacket and bearing having interrupted threads permitting the latter to be readily engaged with or disengaged from the former, a lock nut carried by the bearing and having threaded engagement with the thread thereof, a lock ring longitudinally movable relatively to the bearing but held against rotation relatively thereto, the said lock ring having longitudinal serrations on its periphery and being positioned to be pressed by the lock nut against the end of the jacket when the bearing and jacket are in normal relationship, and a resilient latch on the jacket for engaging any one of the serrations on the ring to prevent relative rotation of said ring.

FREDERICK T. MOORE. 

